<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>出现滚动条</title>
  <style>
    .zone{
      background-color: silver;
      width: 120px;
      height: 150px;
      overflow: auto;
    }
  </style>
</head>
<body>
<div>
  <ul class="zone" id="zone">
    <li>0</li>
    <li>1</li>
    <li>2</li>
    <li>3</li>
    <li>4</li>
    <li>5</li>
    <li>6</li>
    <li>7</li>
    <li>8</li>
    <li>9</li>
  </ul>
</div>

<script>
  let element = document.getElementById("zone")

  // element.onwheel = function(e){
  //   console.log(e);
  // }

  element.onscroll = function(e) {
    console.log(e);
  }


</script>
</body>
</html>